This invention relates to variable magnification or zoom lenses, and more particularly to a zoom "half lens" or reflector lens capable of operation as the equivalent of a full lens having twice as many elements in symmetrical form. In copending application Ser. No. 663,397 filed concurrently herewith in the names of Price and Spurles, a variable magnification lens is disclosed which includes a symmetrical arrangement of outer crown elements, inner flint elements, and innermost meniscus elements. The crown elements are stationary with each flint-meniscus pair movable as a unit to vary the magnification. The movements of the flint-meniscus pairs are symmetrical as are the lens elements themselves. The perfect symmetry of the lens described in that copending application renders the lens usable in a reflector lens mode, that is with a reflector at the lens center by which to fold the optical axis back through the "front" half of the lens as an economical substitute for the back half of the lens. A reflector lens of unity magnification is disclosed, by way of background, in U.S. Pat. No. 3,659,922 issued to George L. McCrobie.
It is an object of this invention to provide a variable magnification reflector lens.
Other objects, advantages, and features of this invention will become apparent from the following more detailed description of an exemplary embodiment given in connection with the accompanying drawing.